[Boost-users] MSVC compiler error with boost ver 1.71

Hi there - I'm using boost ver 1.71 and I'm seeing a strange problem with VS2019. Simply #including this line at the top of a source file will generate a compiler error if I try to build in Debug mode (Release builds are okay...) #include When I say a "compiler error" I'm not referring to one of the usual CXXXX messages - what happens is this:-

INTERNAL COMPILER ERROR in 'C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\VC\Tools\MSVC\14.29.30037\bin\HostX86\x64\CL.exe' Please choose the Technical Support command on the Visual C++ Help menu, or open the Technical Support help file for more information Done building project "ardour.vcxproj" -- FAILED. ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

Just wondering if anyone else has encountered this..? Thanks, John